Beginning in the 1880’s up until World War Two, hoboes placed markings on fences, posts, sidewalks, buildings, trestles, bridge abutments, and railroad line side equipment to aid them and others of their kind in finding help or steering them clear of trouble. Usually, these signs would be written in chalk or coal letting others know what they could expect in the area of the symbol. The classic American hobo of the late 19th and early 20th centuries communicated through a basic system of markings, a code though which they gave information and warnings to their fellow Knights of the Road.